mental age

American  

noun

Psychology.

1. the level of native mental ability or capacity of an individual, usually as determined by an intelligence test, in relation to the chronological age of the average individual at this level.

   a ten-year-old child with the mental age of a twelve-year-old; a mental age of twelve.

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mental age British  

noun

1. psychol the mental ability of a child, expressed in years and based on a comparison of his test performance with the performance of children with a range of chronological ages See also intelligence quotient

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Etymology

Origin of mental age

First recorded in 1910–15

Compare meaning

How does mental-age compare to similar and commonly confused words? Explore the most common comparisons:

• mental age vs. chronological age

Example Sentences

See Examples For:

mental age

He wanted to know exactly what had happened, but could not ask Aaron, who is non-verbal and whom he describes as having the mental age of a two-year-old.

From BBC ● Jul. 15, 2025

It’s not cute watching and adult man regress to the mental age of a three-year-old.

From Salon ● Mar. 1, 2024

His lawyer, M. Ravi, said Nagaenthran, now 33, “could possibly have a mental age below 18” and that the disability doesn’t allow him to understand or appreciate deterrence.

From Seattle Times ● Nov. 4, 2021

Her mental age was about 5 or 6 years old, her parents said in the claim.

From Fox News ● Jan. 21, 2020

Their mental age ranges from three to seven years inclusive.

From Being Well-Born An Introduction to Eugenics by Guyer, Michael F.